Antialiasing enum

[carewolf]

While text is currently not part of the standard a possible antialiasing technique might still be using sub-pixel rendering. If an image is to be displayed between two different screen or is expected to be rescaled, you don't want subpixel scaling you want generic antialiasin. So you might want to consider instead or in addtional of good/best to have best for device and best for generic.

[mikebmcl]

The current plan is to have a separate enum for text antialiasing. Right now, the four fundamental drawing operations are "paint", "stroke", "fill", and "mask". Rendering text will be the fifth (and final, to the best of my knowledge) operation. Generally, text antialiasing strategies are different from rasterized image antialiasing strategies. So to me it me it makes sense to have separate enum classes for each. But I'm happy to consider arguments to the contrary.

[carewolf]

The argument is more that it could technically make sense to use subpixel antialiasing on non-text rendering. Of course that is not that common.

[mikebmcl]

Graphics technologies that I'm familiar with don't do subpixel rendering for non-text rendering; if they do, they don't expose it via any API.

The nice thing about enum classes is that adding enumerators to them does not break ABI. So if this turns out to be something that should exist either now or in the future, adding it would not cause any breaking changes.

If you think of particular graphics technologies, please do let me know. You can always propose the change yourself, of course, and I'd make it if LEWG came to a consensus that it should be done. But that whole process can be bypassed if you convince me or Guy that it should be done.

Best regards,

-Mike